In oil and natural gas exploration, after a borehole has been drilled and a casing or open hole has been cemented within the borehole, one or more sections of the casing or open hole adjacent pay zones (e.g., reservoirs containing valuable resources, such as oil or natural gas) are perforated to allow fluid from the surrounding formation to flow into the well for production to the surface. Perforating guns are lowered into the borehole and the guns are fired to create openings in the casing or open hole and to extend perforations into the surrounding formation.
A production tubing may be inserted into the borehole to recover the fluid. Sealing devices may be used to seal off or otherwise block the formation and borehole fluids from the annulus between the production tubing and the casing or open hole during recovery of the fluid. Such devices may also be used for performing other operations within the casing or open hole. One such device is known as a packer, which is used in combination with reinforcing material (e.g., wire mesh). The packer may include at least one inflatable element that is used to seal off the passageway defined by the casing or open hole. One of the shortcomings associated with the use of packers is that the inflatable element may be subject to being extruded through the reinforcing material when the device is exposed to increased axial pressures and/or temperatures caused by the fluid.
The present invention relates, in part, to systems and techniques used to seal off the borehole during production or other operations. Of course, such systems may be used to block or otherwise seal other passageways as well. The systems may relate to anchoring systems that can be used to hold other components, such as logging tools, in specific positions within the well. The systems may also relate to crawling systems used to convey tools in horizontal and deviated wells.